I am NOT a programmer, but I am attempting to put together a dropdown listing for our company's website. It's a very simple operation, but I'm struggling figuring out how to make it work.

I have it partially working.

The idea is the list all of the tires that we have in our inventory so that customers know what we have for them. We want to have 3 (possibly add more later) dropdown menus that allow a person to choose the width, sidewall, and rim size. That will then sort information from a MySQL database and display it to the customer. (This way they can see all of the R16 tires we have. Or all of the 70/R16, or all of the 175/90/R15, etc.)

While looking around online (and on this site) I've found quite a bit of useful information that I've been able to use to get things going.

Right now my database is called names and has the tables: Width, Sidewall, Rim.

I am able to get the dropdown menus to populate correctly.I am able to get the Width dropdown menu to work correctly.The Sidewall (Height) and the Rim do not work and I have NO clue where to go next to attempt to get them to work.

If the database design is wrong then everything else will be far more complicated than it needs to be. Are you sure that you have a fully normalized database? If not then making sure that the database design is fixed would be the first step.